A transparent tunnel so elephants and trains never meet

Bibek Ghosh lives in Birpara, in the Dooars. Between 2019 and 2023, he says, Alipurduar lost 20+ elephants to trains. "One elephant death breaks the forest," he says, and collisions put human lives at risk too.

The fixes he sees around him are reactive: forest guards playing honeybee sounds, or railways reducing speed after an accident. He wanted a proactive design, one "where elephants and trains never meet." That is what the Smart Adaptive Railway Tunnel System, S.A.R.T.S, is meant to be. The goal, as he states it, is zero wildlife mortality while trains run at full operational speed.

“Daily I see tea gardens, Buxa hills, elephants. But tracks bring death.”

Bibek Ghosh

The design has three tiers. Indian railway terrain, he says, is not uniform. In steep corridors like Buxa and Gulma, the tracks would run inside an elevated transparent tunnel, leaving the ground migration paths open underneath for elephants. On the plains around Birpara and Banarhat, where elevating tracks is too costly, a surface-level transparent acoustic tunnel would be built over the existing tracks to block train noise and headlight glare. At existing underpasses, modular shielding panels would stop animals climbing onto the tracks.

On paper the tunnel is a multi-layered composite shell, built to withstand up to 60 kJ of impact, which he sets against an adult elephant's charge, estimated at 50 kJ. Solar roof tiles would power it. Instead of external sensors, the concept uses a software update to the railway's existing Track Circuit Voltage Monitoring system to track train positions. By his cost model, one kilometre of mixed terrain comes to 12.0 Cr INR.

He wants SARTS to protect the 10 most critical hotspots in North Bengal first, then Assam and Kerala, then Africa and the Amazon. "By 2030, we can make modern transport networks completely safe for biodiversity," he says.

"SARTS is my definitive answer to the tragic newspaper headlines I grew up reading in Birpara," he says.